高效光热催化废旧聚酯塑料升级回收  

Highly efficient photothermal catalytic upcycling of polyethylene terephthalate via boosted localized heating

作　　者：娄向西 高璇[2] 刘钰 褚名宇 张丛洋 邱盈华 杨文秀 曹暮寒 王贵领 张桥[2] 陈金星 Xiangxi Lou;Xuan Gao;Yu Liu;Mingyu Chu;Congyang Zhang;Yinghua Qiu;Wenxiu Yang;Muhan Cao;Guiling Wang;Qiao Zhang;Jinxing Chen(Key Laboratory of Superlight Materials and Surface Technology of Ministry of Education,College of Materials Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,Heilongjiang,China;Institute of Functional Nano&Soft Materials(FUNSOM),Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices,Soochow University,Suzhou 215123,Jiangsu,China;Analysis and Testing Center of Southeast University,Southeast University,Jiulonghu Lake Campus,Nanjing 211189,Jiangsu,China)

机构地区：[1]哈尔滨工程大学材料科学与化学工程学院,超轻材料与表面技术教育部重点实验室,黑龙江哈尔滨150001 [2]苏州大学功能纳米与软物质研究院,江苏省碳基功能材料与器件重点实验室,江苏苏州215123 [3]东南大学分析测试中心,江苏南京211189

出　　处：《Chinese Journal of Catalysis》2023年第6期113-122,共10页催化学报（英文）

基　　金：国家自然科学基金(51901147);江苏省碳基功能材料与器件重点实验室(ZZ2103);姑苏创新企业领军人才计划(ZXL2022492);111项目;苏州大学生创新创业训练计划(202210285038Z).

摘　　要：太阳能是一种绿色、清洁的能源.将可再生太阳能转化为热能驱动聚酯醇解反应,即发展光热催化聚酯醇解方法,实现废弃塑料转化为高纯度、高附加值单体,有望解决传统热催化体系效率低、能耗高的问题,实现废弃塑料的高效增值回收利用.一方面,光热催化体系可满足传统热催化所需的反应温度,同时光热催化过程中存在的局域热效应,可进一步提升聚酯回收的催化活性,保障聚酯的高效醇解.另一方面,利用太阳能驱动光热催化聚酯醇解反应,不仅降低能耗,减少CO_(2)排放,还可以充分利用清洁能源,实现太阳能到化学能的高效转化.然而,催化剂的光热转化效率低、局域热效应弱以及催化活性低是限制其发展的挑战问题.本文采用模板法合成了ZIF-8纳米粒子,在ZIF-8表面包覆一层SiO_(2),经高温处理后得到一体化光热催化剂.内部碳材料在吸收太阳光后产生热能,而外层SiO_(2)可以阻止内部热的辐射损失,从而提高局域温度.此外,SiO_(2)包覆层可以抑制c-ZIF-8在高温热解过程中的聚集,使催化剂在催化反应过程中具有更好的分散性.优化后的光热催化剂(c-ZIF-8@25SiO_(2))在0.78 Wcm-2模拟太阳光照射30 min下的PET转化率为84.97%,是热催化反应性能的3.4倍.当反应时间延长至45 min时,PET转化率达到100%.动力学分析表明,光热催化PET醇解的活化能为59.35 k Jmol-1,低于大多文献报道值(通常>70 k J mol-1),更重要的是,其活化能也与热催化PET醇解的活化能(61.04 k Jmol-1)相近反应.上述结果表明,c-ZIF-8@25SiO_(2)纳米颗粒光热催化PET醇解和热催化PET醇解的反应路径可能是相同的,因此排除了光化学活化在光热催化中的贡献.此外,这种SiO_(2)包覆层也使内部催化剂具有较高的稳定性,其中PET转化率和对苯二甲酸乙二醇酯产率在5次循环后分别保持在初始值的98%和95%.在室外太阳光照射下进行PET醇解实验以及从混�Photothermal catalysis driven by clean solar energy efficiently converts plastic waste into high-value-added products.The catalytic process involves the transformation of solar energy to chemical energy.However,designing photothermal catalysts with a high conversion efficiency and catalytic activity remains considerably challenging.In this study,a c-ZIF-8@SiO_(2)nanostructure is fabricated.It acts both as the photothermal reagent and the catalyst,displaying high photothermal conversion efficiency,catalytic activity,and stability in polyethylene terephthalate(PET)glycolysis.SiO_(2)-coated c-ZIF-8 effectively reduces the thermal radiation loss of the carbon material,thus enhancing the local thermal effect of the catalytic system.Consequently,the conversion efficiency of PET achieved using photothermal catalysis is 3.4 times higher than that of thermal catalysis under the same conditions.An economic efficiency analysis proves that photothermal catalysis can save 6390000 kW·h of electricity and reduce up to 3089.59 tons of CO_(2)emissions for every 10000 tons of PET recycled.Therefore,the development of clean energy-driven photothermal catalysis technology could be a potential solution for the upcycling of waste plastics.

关 键 词：光热催化 局域热效应 聚酯升级回收 聚酯醇解 金属有机框架 

分 类 号：TQ426[化学工程] X705[环境科学与工程—环境工程]